Old GPO logon script is still running on clients?

An old GPO logon script is still running on clients, eventhough it has long been disabled/deleted. It was a simple batch file that created a shortcut on client desktops. How do I make it stop doing this?

This tutorial will walk an individual through the process of configuring their Windows Server 2012 domain controller to synchronize its time with a trusted, external resource.
Use Google, Bing, or other preferred search engine to locate trusted NTP …